Diagnostic accuracy of acute maxillary sinusitis in adults in primary care

Objective - To evaluate the diagnostic value of symptoms and signs used in diagnosing acute community-acquired maxillary sinusitis (ACAMS), and to find useful clinical predictors for diagnosing it in adults in primary care. Design - Prospective study in the study group and retrospective study in the reference group. Setting - One primary care centre in the study group and another in the reference group. Subjects - 50 adults with prolonged upper respiratory tract infection ( &#83 7 days) or self-suspected maxillary sinusitis. As a reference group, an analysis of records and diagnoses made by GP of 45 adult patients with the same inclusion criteria from another primary care clinic. Main outcome measures - The signs and symptoms associated with the diagnosis of ACAMS by GP and otorhinolaryngologist. The value of CRP, ultrasound and peak nasal expiratory flow in the diagnosis. Results - Neither ultrasound nor any of the clinical signs increased the accuracy of diagnosis. Peak nasal expiratory flow below the normal range was associated with the diagnosis of ACAMS (p = 0.03). The presence of an otorhinolaryngologist had an influence on GP practice when compared with the reference group. Conclusion - The diagnosis of ACAMS is difficult with the available clinical methods. Peak nasal expiratory flow needs further study. New diagnostic means are needed.